The diagnostic value of neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio in severe Mycoplasma pneumoniae pneumonia / 中华实用儿科临床杂志

ABSTRACT

Objective:To study the value of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in diagnosing severe Mycoplasma pneumoniae pneumonia (MPP).Methods:A total of 616 cases of MPP patients in the Children′s Hospital of Soochow University from January 2015 to December 2017 were retrospectively analyzed.During the same period, 100 healthy children were selected as the healthy control group.NLR and PLR between MPP group and healthy control group, and those between severe MPP group and ordinary MPP group were compared by t test or rank sum test.Risk factors for severe MPP were identified.Receiver operating characteristic(ROC) curves were plotted to identify the cut-off point of NLR and PLR in distinguishing MPP from healthy subjects. Results:(1)The median of white blood cell count (WBC), neutrophil count (N), platelet count (PLT), NLR, PLR, immunoglobulin M (IgM) and the median percentage of CD3 -CD 19+ , CD 19+ CD 23+ in MPP group were significantly higher than those in healthy control group(8.36×10 9/L vs.7.49×10 9/L, 4.41×10 9/L vs.3.11×10 9/L, 340.92×10 9/L vs.234.00×10 9/L, 1.70 vs.0.91, 112.99 vs.70.34, 1.33 g/L vs.1.29 g/L, 20.95% vs.17.10%, 11.25% vs.9.70%), whereas the median of lymphocyte count (L), IgA and the median percentage of CD3 + , CD3 + CD8 + , and CD3 -CD +(16+ 56) were significantly lower(2.64×10 9/L vs.3.37×10 9/L, 0.86 g/L vs.1.30 g/L, 64.55% vs.68.00%, 23.65% vs.24.90%, 10.50% vs.12.20%)( Z=-3.074, -2.413, -2.972, -1.357, -1.863, -2.251, -4.282, -3.420, -2.221, -4.181, -2.784, -2.024, -2.791, all P<0.05). (2)The median of N, NLR, PLR, IgA, IgG, IgM and the average of percentage of CD3 + , CD3 + CD8 + in severe MPP group were significantly higher than those in ordinary MPP group[5.18×10 9/L vs.3.52×10 9/L, 2.39 vs.1.03, 149.32 vs.94.23, 1.29 g/L vs.0.71 g/L, 9.63 g/L vs.8.19 g/L, 1.40 g/L vs.1.29 g/L, (65.53±9.75)% vs.(62.81±9.89)%, (25.35±6.65)% vs.(23.38±6.91)%], whereas the median of L, the median percentage of CD3 -CD 19+ , and CD 19+ CD 23+ were significantly lower than those of ordinary MPP group(2.02×10 9/L vs.3.25×10 9/L, 17.40% vs.21.50%, 9.00% vs.11.70%)( Z/ t=-7.807, -11.313, -10.452, -8.819, -6.162, -3.047, -3.128, -3.270, -9.402, -5.191, -5.214, all P<0.05). (3)Univariate and multivariate Logistic regression analysis showed that CD3 -CD 19+ was the protective factor for severe MPP, while N, NLR and PLR were the risk factors for severe MPP (all P<0.05), with the risk sequence of NLR>PLR>N.(4)Area under ROC curve analysis of NLR and PLR in the diagnosis of severe MPP NLR AUC=0.789, 95% CI 0.754~0.823, P<0.001; PLR AUC=0.767, 95% CI 0.730~0.804, P<0.001; when the critical value of NLR was 1.09, the sensitivity was 98.9%, and the specificity was 70.6%.When the critical value of PLR was 97.47, the sensitivity and specificity were 88.5% and 69.4%. Conclusions:NLR and PLR can be served as independent influencing factors for severe MPP, showing the diagnostic potential in severe MPP.